395nm UV Torch for Isopods, Millipedes & Inverts

Switch off the lights, click this on, and a shelf of everyday invertebrates can turn into something out of a fairground. A pocket ultraviolet torch is one of the small joys of the hobby: it lifts out a layer of colour that is present all the time but stays invisible under ordinary light, and it makes a late-night look at your cultures feel like an event.

It helps to know what is actually happening here, because it is better than the usual "glow in the dark" shorthand. The animals are not making their own light. What you are seeing is fluorescence: the torch floods them with ultraviolet, parts of the shell soak it up and throw it back as visible colour, and the instant you switch off, the effect is gone. True light-making, the bioluminescence of a firefly, is a rarer and separate thing. Here you supply the ultraviolet and the animal answers it, which is exactly why the torch is the thing that unlocks the show.

Scorpions are the classic demonstration, blazing electric blue-green under UV, but plenty of the animals we keep join in to their own degree. Some millipedes are the stars of it, our Hawaiian Glow Millipede among them, and many isopods carry a softer fluorescence, some far more than others. Run the beam slowly across a bioactive tub and you will usually turn up a few surprises: a fleck of fungus, a mineral in the substrate, a hidden marking on a shell. How much you see comes down to the species and to letting your eyes settle into the dark.

The torch itself is a slim aluminium pen light, small enough to live in a pocket or a kit drawer, with a metal clip, an anti-slip grip and a single press for on and off, so there are no modes to cycle through. The beam is a 395nm ultraviolet, the common and affordable UV wavelength, so expect the faint violet cast that comes with 395nm alongside the fluorescence it brings out. It runs on ordinary AAA batteries, so there is nothing unusual to source.

Using it well takes almost nothing. Wait until the room is fully dark, hold the torch a little back from the enclosure, and give your eyes a few seconds to adjust as the colours build. Two sensible cautions come with any UV light: do not shine the beam into your eyes or anyone else's, and treat viewing as a short pleasure rather than leaving animals sitting under ultraviolet, which is stressful to small invertebrates over time. A minute under the torch is a treat; a permanent fixture it is not.

I have added this torch to the accessories range specifically for invert keepers, so it sits with the animals it shows off and the rest of your kit. It pairs naturally with the featherlight tweezers in the maintenance drawer and gives you a fresh way to look at everything on the isopods and millipedes shelves. Have a look through the full accessories range for the rest, and reach for the torch whenever you want to see what your inverts have been hiding.